Bluetao

🚧 Work in Progress - v0.1.0

A functional library focused on working with iterables.

Example

import { map, filter, pipeline } from "jsr:@justbyitself/bluetao"

// Same code works on different types
const transform = pipeline([
  filter(x => x > 2),
  map(x => x * 2)
])

transform([1, 2, 3, 4])           // [6, 8]
transform(new Set([1, 2, 3, 4]))  // Set { 6, 8 }

Same example in plain JavaScript

// Without Bluetao, you need different code for each type

// For arrays - easy
const arr = [1, 2, 3, 4]
const resultArr = arr.filter(x => x > 2).map(x => x * 2)
console.log(resultArr) // [6, 8]

// For sets - manual conversion
const set = new Set([1, 2, 3, 4])
const resultSet = new Set(
  [...set].filter(x => x > 2).map(x => x * 2)
)
console.log(resultSet) // Set { 6, 8 }

Same example in plain JavaScript (imperative style)

// Arrays
const arr = [1, 2, 3, 4]
const resultArr = []
for (const x of arr) {
  if (x > 2) resultArr.push(x * 2)
}
console.log(resultArr) // [6, 8]

// Sets
const set = new Set([1, 2, 3, 4])
const resultSet = new Set()
for (const x of set) {
  if (x > 2) resultSet.add(x * 2)
}
console.log(resultSet) // Set { 6, 8 }

Motivation

For Users (Developers)

• Polymorphism: Same functions work on arrays, sets, maps, strings, and more
• Composition: Curried, data-last functions compose naturally
• Type preservation: Operations return the same type they receive
• Consistency: Unified API across all collection types, fixing JavaScript's inconsistent built-in methods
• Readability: Express transformations declaratively

For Bluetao Developers

• Implement polymorphic functions without repetitive type checks
• Leverage Morphity, a trait-based system, to handle polymorphism cleanly

TODO

• Improve documentation
• Add more functions